Vacuum carpet comb for shag rugs

ABSTRACT

Dual purpose cleaning tool comprising cylindrical suction head, tubular outlet, and depending nozzle means. In preferred form, nozzle means takes form of individual tubes joined to head on tangent to cause smooth flow and rotation on way to outlet along spiral path. The path produces injector pumping action. The spaced, parallel tubes act as rake or comb to untangle shag rug pile while cleaning. In a modification, nozzle means is an elongate single enclosure for use with short pile carpets, and is connected to suction head in the same way.

United States Paten Clewett Oct. 23, 1973 VACUUM CARPET COMB FOR SHAG RUGS Inventor: Raymond W. Clewett, 7069 Fernhill Drive, Malibu, Calif. 90265 221 Filed:

Int. Cl.

Y is fiiiiz Appl. No.: 221,654

References Cited U.S. CI. 15/397 A47l 9/06 Field of Search 15/393, 396, 397,

UNITED STATES PATENTS Johnson Primary Examiner-Harvey C. Hornsby Assistant Examiner-C. K. Moore Att0rneyWarren L. Patton ABSTRACT 14 Claims, 5 Drawing Figures PATENIEDncI 23 1975 70 MCUUM 5,46

VACUUM CARPET COMB FOR SHAG RUGS BACKGROUND OF THE INVENTION This invention lies in the field of vacuum or suction cleaners for carpets and the like, and is directed to an improved cleaning tool which attains maximum power and cleaning efficiency with a given suction source. It is more particularly directed to a cleaning tool which performs the functions of a shag rug pile-untangling rake or comb with a special deep cleaning action.

The carpeting known as shag is a floor covering material consisting of many closely spaced, uniform length, loosely twisted fiber strands that have been woven into a backing, or base fabric, in such a manner that the individual strands (usually about 1%; inches long) stand independently erect. In use, these strands are flattened and eventually become entangled and matted to where they will not spring back after being stepped on. In areas of heavy traffic we find the strands no longer standing erect but lying flat, with dust and lint trapped beneath them.

Conventional nozzles for vacuum cleaning carpets are of two types, both designed primarily for cleaning short pile or loopwoven carpets. The most common nozzle is a shaped vacuum chamber with a long narrow slot along the bottom 'side. When this slotted opening is drawn over the carpet, dust and dirt are picked up from the surface and drawn into the vacuum cleaner bag. The second type of nozzle is similar to the first, but with the addition of a mechanical brushing or beating device to aid in loosening the dirt from the carpet fibers so it will be more readily picked up .by the flow of air created by the vacuum. I

In the vacuum cleaning of shag carpets, both types of nozzle have the same faults. They are not capable of removing dirt that is trapped under flattened shag strands. They do not lift flattened shag strands to the full erect position that releases trapped dirt for removal, and returns the carpet to its original appearance and condition. Nozzles equipped with mechanical beaters have an additional problem. They are designed for short pile carpets and the relatively long strands of shag become entangled and damaged in the beating mechal'llSm.

SUMMARY OF THE INVENTION The cleaning tool of the present invention overcomes the difficulties mentioned above and provides a simple device which removes the tangles of the shag pile, cleans the individual strands, and applies dirt-removing air flow directly to the rug backing for maximum cleaning, and requires no moving parts. The components of the tool are a suction head in the form of an elongate cylinder, a tubular airflow outlet, and a plurality of depending inlet tubes.

The tubes are arranged in a general plane extending I helical or spiral paths toward the outlet, which is also arranged in tangent relation and facing in a direction to receive the air streams in a generally straight line relation.

The extended spiral path increases the velocity of the air streams, which increases the cleaning action, and the flow of the rotating air past the inlet ends of the tubes produces a pumping action in the nature of an injection system, which, in turn, increases the energy of the air streams. The depending spaced tubes which are substantially rigid serve as a comb or rake to untangle the shag pile in the same manner as the single purpose rakes presently used for this necessary function.

The usual practice is to rake the entire rug or carpet prior to cleaning in order to present as open a pile as possible. The standard cleaning tool is then used, but it flattens the pile as it progresses and applies the cleaning action only to the flattened upper surface, while the major portion of the dirt and abrasive material lies on the backing under the strands and is not picked up. With the present tool, the rake tooth tubes straighten the pile and penetrate readily to the backing so that the air flow into their lower ends picks up the foreign matter on the backing.

As the comb is drawn across the carpet and the strands are disentangled, they are drawn into the tubes by the high velocity inlet air. While in this high speed air stream, the strands are drawn fully erect, whipped, fluffed, and cleaned. As the comb moves on across the carpet, the strands emerge from cutout sections at the back of each tube and are left standing erect, fluffy, and clean. The inside diameters of the tubes are larger than the carpet strands, but small enough that the total intake area of all the tubes is no greater than the intake area of the vacuum cleaner, and preferably somewhat smaller.

In a modification for use with short pile carpets, the series of tubes is replaced with a single elongated enclosure, open at top and bottom, to define one long narrow inlet tube which is mounted in the same attitude to an identical suction head. The size and shape of the nozzle produce maximum cleaning air flow on and through the short pile.

BRIEF DESCRIPTION OF THE DRAWING Various other advantages and features of novelty will become apparent as the description proceeds in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of the total cleaning tool in operation;

FIG. 2 is a sectional view taken on line 2-2of FIG.

FIG. 3 is a partial front elevational view taken in the direction of arrow} of FIG. 2;

FIG. 4 is a bottom plan view of one comb tooth taken in the direction of arrow 4 of FIG. 3; and

FIG. 5 is a bottom plan view of a modified form of cleaning tool.

DESCRIPTION OF PREFERRED EMBODIMENTS The cleaning tool 10 in its entirety is shown in operation in FIG. 1, where the comb or rake type device is applied to a carpet 12 having a backing 14 with a generally tangled and matted pile 16, the tool being pulled rearward in the direction of arrow 18 to clean and realign the pile, as indicated at 20. Although the pile is shown schematically as single filaments for ease of illustration, an actual shag carpet strand is approximately ts inch in diameter, 1 to 2 inches long, and made up of dozens of individual fibers that have been loosely twisted or woven together.

The main components of the cleaning tool are the suction head 22 in the form of an elongate substantially cylindrical casing having end closures 24, which may be caps or plugs, to define an enclosed vortex chamber 26, a tubular airflow outlet 28 for connection to a wand 30 leading to a suction source, and downwardly depending nozzle means 32. Preferably, suitable means, such as a removable end closure, are provided to facilitate cleaning out lint, etc., which may remain lodged in chamber 26.

In the preferred embodiment, the nozzle means comprises a plurality of tubes 34 lying in a general plane which is substantially vertical in operative position, with the tubes extending generally vertically and arranged in spaced parallel relation. The general plane is substantially tangent to the forward portion of the wall 36 of the suction head, and the upper end 38 of the tubes are spaced along the major portion of the length of the head and are secured thereto, projecting through wall 36 so that the inlet air passages 40 open into the vortex chamber with their inner from surfaces substantially tangent and adjacent the inner wall of the chamber. The maximum cross-sectional dimension of the upper ends 38 of the tubes is considerablly smaller than the diameter of the suction head, so that the individual streams of inlet air rotate at high velocity around the inner wall. Since most of the ends 38 are laterally displaced from outlet 28, the majority of the inlet streams not only rotate but follow a helical or spiral path from their tube ends to the outlet.

Preferably, inlet ends 38 project into the chamber so that the rotating and spiraling air flow past these ends is substantially parallel to the inlet flow. The rotating flow therefore produces a pumping action which adds energy to the inletstream to increase the cleaning action. Thus, the arrangement of the projecting tubes with the chamber may be said to define an injector system.

The tangent arrangement of the tubes with respect to the suction head insures very smooth entry of the air streams into the chamber, and the rotating and spiral movement toward the outlet continues the smooth flow. Outlet 28 is also arranged on a tangent with the suction head and faces into the rotating flow so that the air is received in a generally straight line relation. The lack of turbulence throughout the system results in maximum flow efficiency and cleaning effectiveness.

Each tube is substantially of constant cross-sectional area throughout its length. It may be circular or. oval in the upper portion, but the lower end 42 is preferably made oval with the major axis perpendicular to the general plane of the tubes, and wedge-shaped, as shown at 44 in FIG. 4, at the side of the general plane adjacent the axis of the head to facilitate penetration of the tangled and matted pile 16 down to backing 14, as indicated in FIG. 2. Thus, the nozzle means serves the dual purpose of raking or combing the pile and also removing foreign material from the backing.

Each tube is also cut away at 46 at the side of the general plane remote from the axis of the head for a dual purpose. The clearance created by this shape facilitates penetration of the mat and also provides access for the entry of the cleaning air and several strands of the pile, as well as ready release of the strands. The cut may be angular, as shown, or concavely curved to minimize the size of wedge portion 44. In either case, it provides a high release point, while most of the inlet area is quite close to the lower end to insure substantial air flow close to the backing.

An important feature of the present construction is the manner in which the individual strands are treated. As the tool is pulled in the direction of arrow 18, the matted strands are disentangled and straightened, and as each tube passes a given point, several strands are drawn into the tube where they are straightened and whipped by the air stream to effectively remove the dirt. This action also fluffs them and restores them to their original form. Since the trailing side of the entry opening is relatively high, the strands emerge readily and retain their straightened and upright attitude. The action is further improved by the fact that the presence of several strands in a tube at one time greatly decreases the open flow path area so that the velocity of the air flow in the region of these strands is greatly increased, which, in turn, increases the effectiveness of the treatment.

While short pile carpets do not need combing, they are nevertheless most effectively cleaned by the use of a nozzle means which produces maximum air flow velocity for a given amount of suction power. The modification shown in FIG. 5 provides all of the benefits of the present invention, except the combing action. In this form the nozzle means takes the form of an elongate enclosure 48 open at its upper and lower margins and extending in a generally vertical plane in operative position, with its inlet air passage means 50 long and very narrow and generally rectangular in cross-section. The upper margin of the enclosure extends along the major portion of the length of suction head 22 and is attached to it in tangent relation in the same way as the nozzle means 32 of FIG. 2.

While the upper opening of passage means 50 is a long narrow port emitting the air as a sheet, the individual particles of air act in the same way as in the first form. They spiral toward the outlet and produce the same injector action as they repeatedly pass the inlet port at high velocity. Consequently, this form provides the same high air flow efficiency and cleaning effects as the first form for use with conventional carpeting.

As previously stated, the total cross-sectional area of the inlet air passage means should not be more than the cross-sectional area of the airflow outlet, and preferably should be less, to achieve high velocity. It has been determined that very good results are achieved when the inlet area is about three-fourths of the outlet area. In order to achieve good vortex or rotational flow in the suction head, the maximum dimension of the upper end opening of the nozzle means perpendicular to its general plane should be a small proportion of the diameter of the suction head. This dimension should be of the order of 15 to 20 percent of the inside diameter of the suction head. In order to accommodate a plurality of strands within an inlet tube at one time and treat them effectively, the inlet passage should have a diameter of 3/8 to 1% inch, or a comparable cross-sectional area in the event of a non-circular tube.

I claim:

1. A carpet cleaning tool comprising:

a suction head provided with a tubular airflow outlet for connection to a conduit leading to a suction source and with downwardly depending nozzle means;

the suction head being in the form of a substantially cylindrical hollow elongate tube provided with end closures and having its longitudinal axis extending laterally of the operative path of movement across a carpet;

the nozzle means lying in a general plane which is substantially vertical in operative position and defining substantially vertical inlet air passage means of substantially constant cross-sectional area which is considerably less than the area of the suction head;

the upper portion of the nozzle means extending along the major portion of the length of the suction head and secured thereto with its front inner surface being substantially tangent to a point on the inner circumference of the suction head and displaced from its longitudinal axis; and

the inlet air passage means opening into the suction head tangent and adjacent its inner wall to cause the entering air to rotate around the inner wall with the major portion of the air following a spiral path to the outlet.

2. A tool as claimed in claim 1, in which at least the aft marginal portion of the upper end of the nozzle means projects into the interior of the suction head to define an injection system.

3. A tool as claimed in claim 1, in which the total cross-sectional area of the inlet passage means is substantially less than the cross-sectional area of the outlet.

4. A tool as claimed in claim 1, in which the total cross-sectional area of the inlet passage means is approximately three-fourths of the crosssectional area of the outlet.

5. A tool as claimed in claim 1, in which the tubular airflow outlet is secured to the suction head in a position with its upper inner surface substantially tangent to a point on the circumference of the head, and opening into the head in a direction to receive the rotating air flow in generally straight line relation.

6. A tool as claimed in claim 1, in which at least one of the end closures of the suction head is removable to facilitate cleaning of the head.

7. A tool as claimed in claim 1, in which the nozzle means is a single elongate enclosure open at its upper and lower margins, and the crosssection of the inlet air passage means is generally rectangular. v

8. A tool as claimed in claim 1, in which the nozzle means comprises a plurality of individual tubes extending generally vertically and arranged in spaced parallel relation to define a comb.

9. A carpet cleaning tool adapted for combing and cleaning shag-type rugs, comprising:

a suction head provided with a tubular airflow outlet for connection to a conduit leading to a suction source and with downwardly depending nozzle means;

the suction head being in the form of a substantially cylindrical hollow elongate tube provided with end closures and having its longitudinal axis extending laterally of the operative path of movement across a carpet;

the nozzle means comprising a plurality of individual elongate hollow tubes parallel to and spaced from each other and lying in a general plane which is substantially vertical in operative position, with their axes extending substantially vertically in the general plane to define a plurality of individual inlet air passages of substantially constant crosssectional area, with the maximum dimensions of the upper ends of the passages perpendicular to the general plane being considerably less than the diameter of the suction head;

the upper ends of the tubes being spaced along the major portion of the length of the suction head and secured thereto with the front inner surface of each of the tubes being substantially tangent to a point on the inner circumference of the suction head and displaced from its longitudinal axis;

the inlet air passages opening into the suction head in a direciton substantially tangent to and adjacent its inner wall and well displaced from its longitudinal axis to cause individual streams of entering air to rotate around the inner wall with the major portion of the entering streams following a spiral path to the outlet; and

the lower free end of each tube being cut away at the side of the general plane remote from the axis of the head to provide access for entry of inlet air and strands of carpet and ready release of the strands.

10. A tool as claimed in claim 9, in which the tubular airflow outlet is secured to an intermediate point of the suction head in a position substantially tangent to a point on the circumference of the head, and opening into the head in a direction to receive the rotating air flow in generally straight line relation.

11. A tool as claimed in claim 9, in which the inner ends of the tubes project into the interior of the suction head to define an injection system.

12. A tool as claimed in claim 9, in which the lower ends of the tubes are wedge-shaped at the side of the general plane which is adjacent the axis of the suction head to facilitate penetration of a tangled carpet pile by the tubes.

13. A tool as claimed in claim 9, in which the total cross-sectional inlet area of the tubes is approximately three-fourths of the cross-sectional area of the outlet.

14. A tool as claimed in claim 9, in which the tubes are substantially cylindrical throughout the major portion of their lengths, and their passage diameters are in the range of 15 percent to 20 percent of the inside diameter of the suction head. 

1. A carpet cleaning tool comprising: a suction head provided with a tubular airflow outlet for connection to a conduit leading to a suction source and with downwardly depending nozzle means; the suction head being in the form of a substantially cylindrical hollow elongate tube provided with end closures and having its longitudinal axis extending laterally of the operative path of movement across a carpet; the nozzle means lying in a general plane which is substantially vertical in operative position and defining substantially vertical inlet air passage means of substantially constant cross-sectional area which is considerably less than the area of the suction head; the upper portion of the nozzle means extending along the major portion of the length of the suction head and secured thereto with its front inner surface being substantially tangent to a point on the inner circumference of the suction head and displaced from its longitudinal axis; and the inlet air passage means opening into the suction head tangent and adjacent its inner wall to cause the entering air to rotate around the inner wall with the major portion of the air following a spiral path to the outlet.
 2. A tool as claimed in claim 1, in which at least the aft marginal portion of the upper end of the nozzle means projects into the interior of the suction head to define an injection system.
 3. A tool as claimed in claim 1, in which the total cross-sectional area of the inlet passage means is substantially less than the cross-sectional area of the outlet.
 4. A tool as claimed in claim 1, in which the total cross-sectional area of the inlet passage means is approximately three-fourths of the cross-sectional area of the outlet.
 5. A tool as claimed in claim 1, in whIch the tubular airflow outlet is secured to the suction head in a position with its upper inner surface substantially tangent to a point on the circumference of the head, and opening into the head in a direction to receive the rotating air flow in generally straight line relation.
 6. A tool as claimed in claim 1, in which at least one of the end closures of the suction head is removable to facilitate cleaning of the head.
 7. A tool as claimed in claim 1, in which the nozzle means is a single elongate enclosure open at its upper and lower margins, and the cross-section of the inlet air passage means is generally rectangular.
 8. A tool as claimed in claim 1, in which the nozzle means comprises a plurality of individual tubes extending generally vertically and arranged in spaced parallel relation to define a comb.
 9. A carpet cleaning tool adapted for combing and cleaning shag-type rugs, comprising: a suction head provided with a tubular airflow outlet for connection to a conduit leading to a suction source and with downwardly depending nozzle means; the suction head being in the form of a substantially cylindrical hollow elongate tube provided with end closures and having its longitudinal axis extending laterally of the operative path of movement across a carpet; the nozzle means comprising a plurality of individual elongate hollow tubes parallel to and spaced from each other and lying in a general plane which is substantially vertical in operative position, with their axes extending substantially vertically in the general plane to define a plurality of individual inlet air passages of substantially constant cross-sectional area, with the maximum dimensions of the upper ends of the passages perpendicular to the general plane being considerably less than the diameter of the suction head; the upper ends of the tubes being spaced along the major portion of the length of the suction head and secured thereto with the front inner surface of each of the tubes being substantially tangent to a point on the inner circumference of the suction head and displaced from its longitudinal axis; the inlet air passages opening into the suction head in a direction substantially tangent to and adjacent its inner wall and well displaced from its longitudinal axis to cause individual streams of entering air to rotate around the inner wall with the major portion of the entering streams following a spiral path to the outlet; and the lower free end of each tube being cut away at the side of the general plane remote from the axis of the head to provide access for entry of inlet air and strands of carpet and ready release of the strands.
 10. A tool as claimed in claim 9, in which the tubular airflow outlet is secured to an intermediate point of the suction head in a position substantially tangent to a point on the circumference of the head, and opening into the head in a direction to receive the rotating air flow in generally straight line relation.
 11. A tool as claimed in claim 9, in which the inner ends of the tubes project into the interior of the suction head to define an injection system.
 12. A tool as claimed in claim 9, in which the lower ends of the tubes are wedge-shaped at the side of the general plane which is adjacent the axis of the suction head to facilitate penetration of a tangled carpet pile by the tubes.
 13. A tool as claimed in claim 9, in which the total cross-sectional inlet area of the tubes is approximately three-fourths of the cross-sectional area of the outlet.
 14. A tool as claimed in claim 9, in which the tubes are substantially cylindrical throughout the major portion of their lengths, and their passage diameters are in the range of 15 percent to 20 percent of the inside diameter of the suction head. 